Fabrication and Physical Evaluation of Gelatin-Coated Carbonate Apatite Foam

Carbonate apatite (CO3Ap) foam has gained much attention in recent years because of its ability to rapidly replace bone. However, its mechanical strength is extremely low for clinical use. In this study, to understand the potential of gelatin-reinforced CO3Ap foam for bone replacement, CO3Ap foam was reinforced with gelatin and the resulting physical characteristics were evaluated. The mechanical strength increased significantly with the gelatin reinforcement. The compressive strength of gelatin-free CO3Ap foam was 74 kPa whereas that of the gelatin-reinforced CO3Ap foam, fabricated using 30 mass % gelatin solution, was approximately 3 MPa. Heat treatment for crosslinking gelatin had little effect on the mechanical strength of the foam. The gelatin-reinforced foam did not maintain its shape when immersed in a saline solution as this promoted swelling of the gelatin; however, in the same conditions, the heat-treated gelatin-reinforced foam proved to be stable. It is concluded, therefore, that heat treatment is the key to the fabrication of stable gelatin-reinforced CO3Ap foam

Primary Thymic Mucosa-Associated Lymphoid Tissue Lymphoma: Diagnostic Tips

AbstractMucosa-associated lymphoid tissue (MALT) lymphoma arising in the thymus is extremely rare and little is known regarding its clinicopathological features. This study examined the clinicopathological features of nine cases of thymic MALT lymphoma. Most patients had autoimmune disease or hyperglobulinemia, and they also had cysts in the tumors. Both increased serum autoantibody levels and polyclonal serum immunoglobulin levels remained essentially unchanged after total thymectomy in all patients. Thymic MALT lymphoma needs to be included in the differential diagnosis in Asian patients with a cystic thymic mass accompanied by autoimmune disease or hyperglobulinemia

Histamine-1 receptor is not required as a downstream effector of orexin-2 receptor in maintenance of basal sleep/wake states

金沢大学医薬保健研究域医学系Aim: The effect of orexin on wakefulness has been suggested to be largely mediated by activation of histaminergic neurones in the tuberomammillary nucleus (TMN) via orexin receptor-2 (OX2R). However, orexin receptors in other regions of the brain might also play important roles in maintenance of wakefulness. To dissect the role of the histaminergic system as a downstream mediator of the orexin system in the regulation of sleep/wake states without compensation by the orexin receptor-1 (OX1R) mediated pathways, we analysed the phenotype of Histamine-1 receptor (H1R) and OX 1R double-deficient (H1R-/-;OX 1R-/-) mice. These mice lack OX1R-mediated pathways in addition to deficiency of H1R, which is thought to be the most important system in downstream of OX2R. Methods: We used H 1R deficient (H1R-/-) mice, H1R -/-;OX1R-/- mice, OX1R and OX 2R double-deficient (OX1R-/-;OX 2R-/-) mice, and wild type controls. Rapid eye movement (REM) sleep, non-REM (NREM) sleep and awake states were determined by polygraphic electroencephalographic/electromyographic recording. Results: No abnormality in sleep/wake states was observed in H1R-/- mice, consistent with previous studies. H1R-/-;OX 1R-/- mice also showed a sleep/wake phenotype comparable to that of wild type mice, while OX1R-/-; OX 2R-/- mice showed severe fragmentation of sleep/wake states. Conclusion: Our observations showed that regulation of the sleep/wake states is completely achieved by OX2R-expressing neurones without involving H1R-mediated pathways. The maintenance of basal physiological sleep/wake states is fully achieved without both H1 and OX1 receptors. Downstream pathways of OX2R other than the histaminergic system might play an important role in the maintenance of sleep/wake states. © 2009 Scandinavian Physiological Society

Effects of demethylating agent 5-aza-2 '-deoxycytidine and histone deacetylase inhibitor FR901228 on maspin gene expression in oral cancer cell lines

Maspin, which belongs to the serine protease inhibitor (serpin) superfamily, has been proposed as a potent tumor suppressor that inhibits cell motility, invasion, angiogenesis, and metastasis. In the present study, we examined the effects of 5-aza-2'-deoxycytidine (5-aza-dC), a demethylating agent, and FR901228, a histone deacetylase (HDAC) inhibitor, on maspin expression in oral cancer cell tines. The expression levels of maspin mRNA were divided into two groups, which was the maspin tow-expressed and high-expressed cell lines in the 12 oral cancer cell lines. The maspin promoter contained only a few methylated CpG sites in the maspin low-expressed cell lines. Moreover, the methylation status was not altered after 5-aza-dC treatment. However, the transcription of the maspin gene was clearly increased following 5-aza-dC treatment in a number of oral cancer cell tines. These results imply that an action of 5-aza-dC is separate from induction of promoter demethylation. Treatment with FR901228 resulted in a time-dependent stimulation of the re-expression of maspin mRNA as early as 4 h after treatment in the maspin downregulated cells. The re-expression of the maspin gene may contribute to the recuperation of biological functions linked to FR901228 such as an inhibitory effect on tumor angiogenesis and cell invasion. These results indicate that maspin and its target genes may be excellent leads for future studies on the potential benefits of FR901228, a HDAC inhibitor, in cancer therapy.</p

歯科用金属アレルギーが疑われる患者の調査

Patients with metal allergy have been increasing due to various metals being used in the daily environment. Therefore, we performed patch tests in 40 patients with suspected metal allergy whose initial visit from April 1992 to march 1996. The medical route to our department and symptoms at the initial consultation at our department were evaluated in all the patients, and the association with oral metals was examined in patients positive for patch tests. The course after treatment was also analyzed. The results were as follows: 1. Fifty percents of the patients were referred to our department from the hospital affiliated to Iwate Medical University. 2. The major symptoms at the initial consultation at our department were eruptions (60.0%), oral mucosal inflammation (23.3%), and tongue pain (13.3%) 3. Patch tests were positive in 27 (67.55%) of the 40 patients. 4. According to metal elements, patch tests were most frequently positive for palladium (10 patients), followed by nickel and cobalt (9 patients each). 5. The positive metal in patch tests was consistent with the oral metal in 20 patients but inconsistent in the other 7. 6. Due to removing antigen metals in the 20 patients , three patients were cured completely, however, rest of the patients showed reduced and recurrent symptoms

Feeding Cues and Injected Nutrients Induce Acute Expression of Multiple Clock Genes in the Mouse Liver

The circadian clock is closely associated with energy metabolism. The liver clock can rapidly adapt to a new feeding cycle within a few days, whereas the lung clock is gradually entrained over one week. However, the mechanism underlying tissue-specific clock resetting is not fully understood. To characterize the rapid response to feeding cues in the liver clock, we examined the effects of a single time-delayed feeding on circadian rhythms in the liver and lungs of Per2::Luc reporter knockin mice. After adapting to a night-time restricted feeding schedule, the mice were fed according to a 4, 8, or 13 h delayed schedule on the last day. The phase of the liver clock was delayed in all groups with delayed feeding, whereas the lung clock remained unaffected. We then examined the acute response of clock and metabolism-related genes in the liver using focused DNA-microarrays. Clock mutant mice were bred under constant light to attenuate the endogenous circadian rhythm, and gene expression profiles were determined during 24 h of fasting followed by 8 h of feeding. Per2 and Dec1 were significantly increased within 1 h of feeding. Real-time RT-PCR analysis revealed a similarly acute response in hepatic clock gene expression caused by feeding wild type mice after an overnight fast. In addition to Per2 and Dec1, the expression of Per1 increased, and that of Rev-erbα decreased in the liver within 1 h of feeding after fasting, whereas none of these clock genes were affected in the lung. Moreover, an intraperitoneal injection of glucose combined with amino acids, but not either alone, reproduced a similar hepatic response. Our findings show that multiple clock genes respond to nutritional cues within 1 h in the liver but not in the lung